ACTG 5039: The primary objectives are: 1) To obtain preliminary data regarding the rates of maintained viral suppression in subjects randomized to ddl/d4T/HU (Arm A) and ddl/d4T/EFV (Arm B) compared to continued therapy with protease inhibitor-containing regimen (Arm C); 2) To compare the frequency of toxicity and treatment intolerance on all three arms; and 3) To obtain preliminary data regarding the rate at which viral suppression can be achieved and maintained with re-initiation of the pre-empty regimen following virologic failure in Arm A or B compared to the rate of maintained viral suppression in Arm C.